Gas turbine engines incorporated in military and commercial aircraft often include variable area exhaust nozzles as well as thrust reversing systems. The thrust reversers are generally required to be add-on equipment which, unfortunately, increases drag and substantially increases the weight and complexity of the engine and/or airframe. Typically, a thrust reverser system comprises a plurality of movable doors or flaps supported and carried by engine case or airframe structure. The doors are either moved by linkages or pivot on hinges into the engine exhaust gas stream to block all or a portion of the gas stream and to redirect the gas stream in a generally forward direction to slow the aircraft.
Some U.S. patents representative of the state of the art of thrust reverser systems are: U.S. Pat. Nos. 2,970,432; 3,153,321; 3,608,314; 3,690,561; 3,973,731; and 4,093,122.